Sectional hot top



July 6, 1948. E. MARBURG sEcTIoNAL Ho'r Tor Filed .April 3' 1947 Patented July 6, 1948 i sEc'rIoNAL no'r Tor Edgar Marburg, Pittsburgh, Pa., assignor to Car- :regie-Illinois Steel Corporation, a corporation of New Jersey Application April 3, 1947, SerialNo. 739,141

Claims. (Cl. 22-147) This invention is a continuation-in-part of my copending application, Serial No. 602,913, led July 2, 1945, now Patent No.-2,433,775, issued December 30, 1947, and relates to a sectional hot top for ingot molds and the like and more par# ticularly to such hot tops for small ingot molds. The walls of hot tops in present use are relatively thick (1% to 2%; in.) which causes the steel to freeze at too slow a rate near the hot top junction and also causes segregation in the ingot. The hot tops now in use have the sides and corners of approximately the same thickness so that the metal in the corner freezes first and continues to freeze faster than the metal at the sides until the interior shape of the frozen metal approximates a circle or ellipse. Thus, the metal in the corners is useless to perform its function. In sectional hot tops the sections in some instances do not closely t the mold walls and the hot metal rises between the hot top and the mold wall causing fins which are objectionable in the rolling of the ingot.

It is an object of my invention to provide a hot top which displaces useless lmetal from the corners of the hot top, thus increasing its efiiciency.

Another object is to provide a hot top having thin walls.

Still another object is to provide a sectional hot top having means for self-wedging all the sections of the hot top against the mold walls.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

Figure 1 is a top plan view of the hot top in place on a mold;

Figure 2 is a sectional View taken on the line 1'I-II of Figure 1; y

Figure 3 is a top plan view of the side slabs in place on a mold shown in broken lines:

Figure 4 is a sectional View taken on the line IV-IV of Figure 2;

Figure 5 is a perspective View of a side slab; and

Figure 6 is a perspective view of an end slab.

Referring more particularly to the drawings,

end of the slab. The central portion of the slab 4 is thin, it being about one inch thick as compared to the ordinary thickness of two or more inches. At each end of the slab 4 is a flange I0 tapering inwardly toward the top, extending outwardly from the mold wall and forming a reinforcement for the slab. A ange I2 is also provided at the top portion of the slab to add transverse strength and prevent longitudinal breakage. A shoulder I4 is provided on each flange I0 and tapers from the top downwardly and inwardly toward the opposite side slab. A second shoulder I6 extending downwardly and outwardly toward the adjacent end wall of the mold is also provided onthe flange I0. Slots I8 are provided in the side slabs 4. A support hook 20 having a hook portion 22 is supported on top of the mold as shown in Figure 2 above each of the slots I8 with the hook portion inserted into the slot I8.

The end slabs 6 have their lower edges bevelled at 24, the outside faces of the bevelled portion having the same contour as the inner surface of the mold. The central portion of this slab is reduced in the same manner as the side slab and a flange 25 is provided at the top portion of the slab to add transverse strength and prevent longitudinal breakage. Flan/ges 26 are provided on each end of the slab 6 and extend toward the opposite end slab. A wedge surface 28 is provided on each flange 28 and faces the shoulders Ill of the side slabs 4 as shown by the arrows in Figures 5 and 6. A second wedge surface 30' is provided adjacent each surface 28 and faces the shoulders I6 of the sla-bs Il as shown by the .arrows in Figures 5 and 6. It will be understood that the surfaces 28 and shoulders I4 have complementary Wedge surfaces. This is also true of the surfaces 30 and shoulders I6.

In assembling a hot top on the mold, a pair of hooks 2U are placed in the openings I8 of each side slab d and the slabs are placed in position and supported from the top of the mold with their lower beveled portion in contact with the mold as the reference numeral 2' indicates the top of a mold on which a hot top is mounted. The hot top consists of two side slabs Il and two end slabs 6. The side slabs have their lower edges bevelled at 8, the outside surface of the bevelled portion having the same contour as the inner surface of the mold, the remaining portion of the outer surface of the slab being flat. The bottom of the side slabs are substantially wider than the top in order to form a wedge surface on each best shown in Figures 2 and 3. The end slabs 8 are then wedged in place in the mold with their surfaces 28 contacting the shoulders I4 of side slabs Il so that the base of the latter is pushed outwardly to contact the mold wall and the surfaces 30 contacting the shoulders I6 of the side slabs 4 so that the end slab is wedged into tight contact with the mold wall. It will be noted that this construction blocks o th'e corners of the hot top to form an irregular elliptical outline of the interior as best shown in Figure 1. Because of in which the slabs have bevelled lower the "arrangement of shoulders Il and IB and wedging surfaces 28 and 30, the bottom of all oi these slabs are in contact with the mold, thus preventing iiow of the hot metal upwardly between the hot top and the mold wall.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modications may be made without departing from the scope of the following claims.

I claim:

1. A sectional hot top for a mold comprising two side andtwo endslabsof refractory material, means for supporting the side slabs on opposite sides oi' 'the mold, each of said side slabs having a pair of shoulders on each end, one of said shoulders tapering downwardly and inwardly toward the opposite side-slab, the second of said shoulders extending downwardly and outwardly toward the adjacent end wall of the mold, the end slabs being located on opposite ends of the mold, each of said end slabs having a pair of wedge surfaces on each end, one of said wedge surfaces being complementary to and in contact with the rst of said shoulders of the side slabs, and the second of said wedge surfaces being complementary to and in contact with the second of said shoulders whereby the bottoms of all the slabs are forced into contact with the mold wall.

2. A hot top for a mold according to claim `1 portions to contact the mold.

3. A sectional hot top for a mold comprising two side and two end slabs of refractory material. means for supporting the side slabs on opposite sides of the mold, each of said side slabs having a pair of shoulders on each end, one of said shoulders tapering downwardly and inwardly tot ward the opposite side slab, the second of vsaid shoulders extending downwardly, and outwardly toward the adjacent end wall of the mold, the

end slabsbeing located on opposite ends of the mold, each of said end slabs having a pair of wedge surfaces on each end, one of said wedge surfaces being complementary to and in contact with the ilrst of said shoulders of the side slabs, the second of said wedge surfaces being complementary to and in contact with the second of said shoulders whereby the bottoms oi' all the slabs are forced into contact with the mold wall. each o! said slabs having thin center portions and thickened end portions.

4. A sectional hot top for a mold comprising two side and two end slabs of refractory material, means for supporting the side slabs on opposite sides of the mold, each of said slabs having thin center portions and outwardly extending vertical anges on each end thereof, each of the flanges on the side slabs having a pair of shoulders thereon. one of said shoulders tapering downwardly and inwardly toward the opposite side slab, the second oi said shoulders extending downwardly and outwardly toward the adjacent end wall of the mold, the end slabs being located on opposite ends of the mold, each of the flanges on the end slabs having a pair of wedge surfaces thereon, one of said wedge surfaces being complementary to and in contact with the ilrst of said shoulders of the side slabs, and the second of said wedge surfaces being complementary to andfin contact with the second of said shoulders whereby the bottoms of all the slabs are forced intocontact with the mold wall.

5. A hot top for a mold according to claim 4 in which the slabs have bevelled lower portions tocontact the x'noloi.4

EDGAR MARBURG.

REFERENCES ClTElD The following references are of record in the Y ille of this patent:

UNITED STATES PATENTS Number 

